//reducer.js
const initialState = {    
  count: 0
}
export function reducer(state = initialState, action) {    
  switch(action.type) {      
      case 'plus':        
      return {            
          ...state,                    
          count: state.count + 1        
      }      
      case 'subtract':        
      return {            
          ...state,            
          count: state.count - 1        
      }      
      default:        
      return initialState    
  }
}